YAML Tutorial - A Complete Language Guide

• YAML stands for YAML Ain't Markup Language

• YAML was created in 2001. Data engineers need to work with YAML

• Many important tools like Ansible and Docker

  

• It is mostly used for configuration files and is seen as a much cleaner alternative to other traditional options like JSON & XML

• YAML uses basic concepts of:

  Keys: Value

• YAML relies on Spacing & Indentation as a result, this approach gives a cleaner and consistent feel

• YAML can be defined by .yaml extension or .yml example <filename>.yml or <filename>.yaml

Example of YAML

team:
  name: Manchester United
  founded: 1878
  stadium: Old Trafford
  location: Manchester, England
​
  leaders:
    - position: Chairman
      name: Joel Glazer Avram Glazer
    - position: Manager
      name: Erik ten Hag
​
notable_moments:
    - year: 1958
      event: Munich air disaster
      description: |
        Tragic plane crash that claimed the lives of several team members.

famous_players:
- Marcus Rashford
- Wayne Rooney
- Christiano Ronaldo

famous_players_2: [Marcus Rashford, Wayne Rooney, Christiano Ronaldo]
​

Compare YAML to JSON

{
   "manchester_united": {
      "name": "Manchester United",
      "founded": 1878,
      "stadium": "Old Trafford",
      "location": "Manchester, England",
      "leaders": [
         {
            "position": "Chairman",
            "name": "Joel Glazer Avram Glazer"
         },
         {
            "position": "Manager",
            "name": "Erik ten Hag"
         }
      ]
   },
   "notable_moments": [
      {
         "year": 1958,
         "event": "Munich air disaster",
         "description": "Tragic plane crash that claimed the lives of several team members.\n"
      }
   ],
   "famous_players": [
      "Marcus Rashford",
      "Wayne Rooney",
      "Christiano Ronaldo"
   ],
   "famous_players_2": [
      "Marcus Rashford",
      "Wayne Rooney",
      "Christiano Ronaldo"
   ]
}

YAML to XML

<manchester_united>
  <name>Manchester United</name>
  <founded>1878</founded>
  <stadium>Old Trafford</stadium>
  <location>Manchester, England</location>
  <leaders>
    <position>Chairman</position>
    <name>Joel Glazer Avram Glazer</name>
  </leaders>
  <leaders>
    <position>Manager</position>
    <name>Erik ten Hag</name>
  </leaders>
</manchester_united>
<notable_moments>
  <year>1958</year>
  <event>Munich air disaster</event>
  <description>Tragic plane crash that claimed the lives of several team members.</description>
</notable_moments>
<famous_players>Marcus Rashford</famous_players>
<famous_players>Wayne Rooney</famous_players>
<famous_players>Christiano Ronaldo</famous_players>
<famous_players_2>Marcus Rashford</famous_players_2>
<famous_players_2>Wayne Rooney</famous_players_2>
<famous_players_2>Christiano Ronaldo</famous_players_2>

In the next section, you will find amazing resources that will help you understand more about YAML

Resources to learn YAML

1. YAML schema reference for Azure Pipelines

2. The YAML file explained

   %[https://www.youtube.com/watch?v=fwLBfZFrLgI]

3. YAML and GitHub actions explained (YouTube)

   %[https://www.youtube.com/watch?v=PwVUVkvcM5A&pp=ygUaaW50ZWdyYXRlIHlhbWwgd2l0aCBnaXRodWI%3D]

You can also delve into DevOps since you will mostly use YAML as a DevOps engineer

1. 90DaysOfDevOps - I recommend this GitHub repo. It will give you better fundamental knowledge about DevOps, especially if you are a beginner

CONCLUSION

Comparing YAML to XML and JSON, we can see that:

• YAML is human-readable and writable - its syntax is clean and simple, and indentation represents hierarchy which in turn reduces the need for complexity of symbols

• YAML is easy to maintain - Slight changes can be made without touching the syntax

• Data Serialization - easy exchange of data between different programs

• It is concise - doesn't require unnecessary punctuation

• Ease of Integration - commonly used in CI/CD pipelines

• Version Control Friendly - can be used with VCS tools such as Git